Field of the Invention
The present invention concerns improvements in and relating to diaphragm pumps.
Description of the Related Art
United Kingdom Patent Specification No. GB 2 352 779 B and European Patent Specification No. EP 1 222 392 B disclose a diaphragm pump comprising a two-part casing formed of a front cover and a back cover; and a diaphragm plate extending across the covers and being secured therebetween when the covers are fastened together. The diaphragm plate has a plurality of circular regions. The front cover has substantially axially aligned inlet and outlet ports, each leading to mutually exclusively inlet and outlet chambers. There is a valve housing securable inside the front cover and having defined therein an outlet dished valve seat with a correspondingly concave resilient outlet valve seated therein, the outlet dished valve seat having fluid passages therethrough, and a plurality of inlet valve seats, equal in number to the number of circular regions on the diaphragm plate, each inlet valve seat being similarly dished and having a correspondingly concave resilient valve seated therein, each inlet valve seat having fluid passages therethrough, the resilient outlet valve being in fluid communication with the outlet chamber and each said inlet valve being in fluid communication with the inlet chamber. The diaphragm pump also includes a wobble plate positioned in the back cover; the wobble plate has a central boss and a plurality of similar piston sections equal in number to the number of circular regions on the diaphragm plate, the piston sections and circular regions being correspondingly secured together, the wobble plate being subject to nutating motion to cause reciprocating action by the circular regions on the diaphragm plate and provide a pumping action.
The present invention relates to improvements to the diaphragm pump disclosed in GB 2 352 779 B and EP 1 222 392 B and provides technical advantages over the previously known diaphragm pumps.